All you need to do is follow your heart. Just draw what you feel.
I saw a wonderful inspirational video, that perfectly showcases how this form of art is simple fun - and intimidating.:
During my research I found some fabulous, more sophisticated zendoodles on a site completely dedicated to the art form aptly called, ZenTangle.
This is my very first zendoodle, but I can already saw I am addicted. I have been carrying my sketch pad with me everywhere, thinking about what my next step would be. My newer works (that are not completed yet), are on a smaller sketch pad, so that won't get cropped in scanning and sharing.
I used the following tools:
